Mac,
I’m an active Instructor and for all intent I often dive alone. I’ve been trained as a solo/self reliant diver and I know factually that a buddy is a safety device among other things and not just a social choice. As for the percentage of diver able to help with a underwater medical emergency. The first step is to get the diver on the surface. Then nearly 100% of divers with a Rescue rating or higher and quite a few without that experience would still be able to assist with a medical emergency at that point.
I know a large number of solo divers but I must say that most would not even attempt to convince others that their choice to dive solo isn’t a higher risk than diving with a experienced buddy. I’m sorry to hear that you believe in that delusion. It’s your choice but it is your life but please stop trying to convince others that you are not delusional. Tardmaster is correct your ego will kill you and a buddy will not be there to save you.